IF your arcade cabinet has a jamma connector you can hook your computer straight to the arcade monitor using a JPac. However, to actually run anything on the arcade monitor you need either software that'll set the right frequency and/or use a card that is capable of the right frequencies.
If you want to run Mame one option is to just boot your computer straight into ArcadeOS through DOS and ArcadeOS will set the right frequency if configured correctly in arcadeos.cfg (incab=1). Go to
www.arcadeos.com for the frontend. Many cards are supported but you should check the support list. You can also use AdvanceMenu which is another front-end that does the same. Many people also choose to use AdvanceMame which is a version of Mame optimized for arcade monitors.
An alternative option is to use a video card that can natively output the right frequencies. One such option and one that is frequently used is a Trident Blade 3d card. With this card you can actually run Windows on your arcade monitor. If you want as little hassle as possible this may be the solution for you.
Decide what you would like to do and then search the site and the message board archives for as much help as possible before asking anything else. Nobody minds the questions, but most of them can be answered by first searching the site.
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